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  <title>Document</title>
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<body>
  <div id="root"></div>
  <script>
    
    const app = Vue.createApp({    
      template:`<div @click="click">{{count}}-{{countAdd}}</div>`,
      setup(){
        const {ref,computed}=Vue;
        const count=ref(0)
        function click(){
          count.value+=1;
        };
        let countAdd=computed({
          get:()=>{
            return count.value+5
          },
          set:(param)=>{
            count.value=param-5
          }
        })
        setTimeout(()=>{
          countAdd.value=100
        },1000)
        return {count,click,countAdd}
      }
    });

    const vm = app.mount('#root');
  </script>
</body>

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